title: [Intrathyroid parathyroid adenomas: right and lower].
abstract: BACKGROUND
  Intrathyroidal parathyroid adenomas (IPA) are a not an uncommon cause of persistent hyperparathyroidism. There is no consensus on their prevalence, embryological origin and position within the thyroid.
  
  
  METHODS
  Retrospective review of prospectively recorded surgical protocols of patients having had parathyroidectomy for primary (n = 437) or secondary (n = 137) hyperparathyroidism by the same surgeon. Cases with IPA were identified and the following data were recorded: age, most probable embryological origin, position within the thyroid (side and height), results of imaging techniques and surgical implications.
  
  
  RESULTS
  Seventeen IPA were detected in 16 patients (6M, 10F, prevalence 3.2%); 9 belonged to IIIP and 8 to IVP. Three lower IPA were supernumerary glands. Eight IPA were included within the right lower thyroid lobe. Twelve IPA (70.6%), were found during the initial parathyroidectomy: 3 were enucleated and 9 were treated with a partial thyroidectomy or hemithyroidectomy. Of the 3 enucleations, 2 had a local benign recurrence due to an incomplete capsule resection. No patients treated with thyroidectomy had a recurrence. The remaining 5 IPA, found in 4 patients, were not identified initially and caused persistence of the disease leading to 5 reinterventions.
  
  
  CONCLUSIONS
  IPA are present in 3% of patients submitted to parathyroidectomy. They predominate in the right thyroid lobe and can be IIIP, IVP and supernumerary. They often cause persistence. Thyroid resection affords the best results since complete enucleation can be difficult and leaving behind a fragment of the IPA results in local recurrence.
authors.affiliation: Unidad de Cirugía Endocrina, Hospital Universitario Arnau de Vilanova, Lleida, España. jrros@telefonica.net
authors.forename: Susana
authors.initials: S
authors.lastname: Ros
authors.forename: Antonio
authors.initials: A
authors.lastname: Sitges-Serra
authors.forename: José Antonio
authors.initials: JA
authors.lastname: Pereira
authors.forename: Jaime
authors.initials: J
authors.lastname: Jimeno
authors.forename: Rosa
authors.initials: R
authors.lastname: Prieto
authors.forename: Juan José
authors.initials: JJ
authors.lastname: Sancho
authors.forename: Luis
authors.initials: L
authors.lastname: Pérez-Ruiz
mesh_terms: D000236:Adenoma / Q000150:complications / Q000000981:diagnostic imaging / Q000601:surgery*; D000328:Adult; D000368:Aged; D000792:Angiography; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D006980:Hyperthyroidism / Q000209:etiology; D008297:Male; D008875:Middle Aged; D018761:Multiple Endocrine Neoplasia Type 1 / Q000601:surgery*; D010282:Parathyroid Neoplasms / Q000150:complications / Q000000981:diagnostic imaging / Q000601:surgery*; D016105:Parathyroidectomy; D012086:Reoperation; D012189:Retrospective Studies; D013964:Thyroid Neoplasms / Q000601:surgery*; D013965:Thyroidectomy; D013997:Time Factors; D015899:Tomography, Emission-Computed, Single-Photon; D016896:Treatment Outcome